Hi.. Thanks for the query. Calcified lump behind the upper incisors on the hard palate is a rare condition which is termed as Mucosal Calcified Nodule that can b due to disturbances in calcium and phosphorus metabolism. Other cause that too is rare is Oral Calcifying Pseudotumor. It needs not to be due to cancer but has very few cases documented in the researches. So it is a must to get a biopsy done to check for the exact nature of the lump.. As it is a very rare condition, but already removed surgically, once the biopsy report comes, please upload it to me so that I can advise you accordingly.. Hope this information helps you. Regards.